Does riding at low intensity really build more capillaries than just riding normal?

Always hear that if you do low intensity riding that is builds the capillaries. I think the recommendations range up to 500 hrs without going into the lactate zone is needed to build more capillaries as the lactate acid is suppose to destroy newly built capillaries. How could that be?

You need to do both long low intensity rides to build up your endurance but you also need to add high intensity intervals to build your lactate threshold and your sprinting muscles. To this mix you must add rest to allow the healing and muscle building process to take place. If you do too much high intensity intervals, you will start to damage your muscles and not allow them time to heal. That may be where you may be getting your information from. Do not neglect the high intensity intervals but do not over do them, no more than 1-2 times a week interspersed with low intensity longer duration workouts and/or rest days.

I've been on two different coaching plans (which were more similar than different) and have read up on others. I have never heard of anything like you are talking about. Just the numbers can't be right. Most training plans consist of no more than 10-12 hours a week max (unless you're a pro) and at your suggestion of 500 hours that means you would be "building capillaries" for 50 weeks out of the 52 week year. I would suggest Joe Friel's "Training Bible" as a great primer on training methods and reasoning._________________Masters 60+;

I visited with a exercise sports physiologist regarding your capillary question and slow endurance training. Yes, the capillaries are built up with slow endurance training. The lactate threshold (the heart rate point at which you can reach maximal lactate build-up tolerance) is built up by the interval training. As I mentioned previously, you have to balance the intervals with endurance training and rest day.

Capillary building will continue with alternating endurance rides with high intensity interval rides. The high intensity intervals provide a stimulus to the muscles fibers that are used for high intensity short burst of power to make more capillaries to deliver more oxygen. The endurance ride will allow you to maximize your capillary development to the muscle fibers that are used for long endurance actvity. Ballance is key and after an extremely intense training day, you should do an easy spinning day or even take a day of rest. It is during the resting or light spinning that your muscles recover and the building of capillares and muscle fibers are maximised. Now, for any of you couch potatoes who may miss quote me to justify full time couch surfing, saying, "The Bike Doc says you gotta rest to build muscles!", you will be way off base. You have to have a ballance of excercise and rest to achieve the muscle building.